Self-sealing conveyer construction



Allg- 14, 1951 H. w. HAPMAN SELF-SEALING CONVEYER CONSTRUCTION 2 Sheets-Sheet 1 Filed March 18, 1947 Aug. 14, 1951 H, W HAPMA'N 2,564,599

SELF-SEALING CONVEYER CONSTRUCTION Filed Mrch 18, 194'? 2 sheets-sheet 2 (ttornegs Patented ug. 14, i951 Henry W. Hapman, Detroit, Mich., assigner, by m'esne assignments, of forty percent :to Hannah VJ. Hapman Application March 18, 1947, 'SerialNo. -'735,401

9 Claims. il

This invention relates to sealing devices and in particular to devices for sealing conveying or 'feeding mechanisms which move ina linear path into or out-of tanks, containers or compartments, as vdistinguished 'from .the sealing of rotating mechanisms, such asshafts `or wheels.

d'One object of this invention is to provide a sealing :device for 'aflinearly-moving conveying or feeding mechanismsuch as .a conveyor .or a reciprocating feeder, so arranged that the mechanism may pass into or out of a compartment under pressure or vacuum, `or containing dust or vapor, without releasing any substantial amount thereof.

vAnother Objectis to provide ya sealing device for alinearly-moving conveying or feeding mechanism, suchas a ilight conveyor, which consists of raxtubular member of. elastic vdeformable material such as .rubber lor'synthetic rubber, subjected to fluid/:pressure vso that it closelyfhugs the flights of the conveyor or the piston head 4of a reciprocating feeder andprevents `leakage either into or out of a compartment which the conveyor or feeder enters or leaves.

Another object is to provide -a .sealing device, as set forth in the preceding objects, wherein the vconveyor'or `feeder mayv operate continuously to convey material into or-out of a compartment without leakage and without requiring the `unloading of the compartment vor container, nor interrupting the operation thereof.

Another object is to provide a sealing device,l as set forth in the preceding objects, for a conveyor arrangedfor the removal of dust from dustcollectors 'or sludge from high tanks, without having to shut down the dust collector or pump theliquid out of the tank.

Another object is to provide ka .sealing device, as set forth in the preceding objects, for a conveyorfor feeder arranged for the feeding of material into .a `compartment under pressure without danger of the material being blown back by the pressure in the compartment, for example, the feeding of pulverized coal to the .pressurized lirebox of a boiler without undergoing any substantial blow back of the coal.

In the drawings:

Figure l is Va central longitudinal section through asealing device for a linearly-moving mechanism consisting of a chain-mounted flight conveyor', according to a preferred form of the invention, with the sealing pressure relaxed;

y Figure 2 is a cross-section through the Adevice shown in Figure` 1, taken along the line 2 2 therein;.

FigureB is a .perspective view of the reinforcing frame for the sealing tube of the sealing device shown in Figures 1 and 2;

Figure 4 is a central longitudinal ,section through a slightly modified sealing device, as

(Cl. ISS-468') v2 employed with a table-mounted flight conveyor;

Figure 5 is a cross-section through the sealing device of Figure 4, taken along'the line 5-5 therein;

Figure 6 is a side elevation, partly in vertical section, of a typical installation, such as an in clined ysludge tank, Vemploying the sealing device and flight conveyor shown in 'Figures 1 lor 4;

Figure 7 is a diagrammatic -side elevation Vof another typical installation, such as a vertical sludge tank, employing the sealing. device and' night conveyor shown in Figures 1 or 4,1Wherein the conveyor is sealed 'both `where it enters yand emerges from the bottom of the tank; and

Figure 8 isa diagrammatic side elevation "of a vertical tank, similar 'to Figure ,'T, but showing an installation 'wherein the conveyor is sealed'only at the vpoint where l-it enters the `tank land passes through van upwardly-.inclined conduit after emerging from'the'tank.

Hitherto, the removal of `sludge .or other deposited matter from tanks, -containers orcompartments under pressure nor under vacuum Yhas presented .serious problems, especially WheniitI is desired vto maintain the Vmachinery inycontinuous.

service without interruption of its operation. In removing the dust from dust collectors operating under pressure, it has hitherto been necessary vvto shut 4down Vthe dust collector in order to remove the dust from it unless "gates -are provided. In feeding pulverized Vcoal to a boiler iirebox which is under pressure, the back pressure has blown the coal back in the direction from which it came, rendering such .installations dirty -and .ineiiicient In removing sludge from the bottom'of :a high tank, such `as an oil tank, Ait has hitherto been necessary to pump out the oil periodically and then enter the tank and clean it out, vthereby subjecting the workman to a dirty and unhealthy task.

The present invention overcomes these difculties by providing a sealing device through which the conveyor or feeder moves upon entering ,and/or leaving the tank, container or compartment. Accordingly, when the invention is applied to -a dust collector operating under pressure, vthe dust can be removed either continuously or intermittently without halting the operation of the dust collector and -without the escape of any considerable quantityof dust into theatmosphere. The present invention also enables pnlverized coal to be fedcontinuously to the pressurized rebox of a `boiler Without resulting in any blow back of the coal, thereby insuring completely successful operation of the `type `of pulverizedcoal burner -which burns the coaland immediately fuses all of the ash therefrom. In removing sludge from the bottom of a high tank full of liquid, such as oil, the present invention enables a conveyor to enter .and leave the bottom of the tank and at the same time to be completely sealed against the pressure arising from the head of liquidin the tank without loss of any substantial portion of the contents of the tank and without requiring the Vtank to be emptied in order for cleaning to be carried out. In an analogous manner, the present invention may also be used to seal the entrance and/or exit of a conveyor or reciprocating feeder which passes through a tank, container or compartment which is under subatmospheric pressure or vacuum.

Referring to the drawings in detail, Figures 1 and 2 show a sealing device, generally designated I9, according to a preferred form of the invention as employed to seal a linearly-moving mechanism such as a chain-mounted night conveyor, generally designated II. The sealing device ID is housed in a tubular housing I2 having connection flanges I3 and I4 which are either integral with the tubular housing I2 or are secured thereto as by welding. The nanges I3 and I4 are bolted as at I5 and I6 to the flanges I1 and I8 of adjacent conduits I9 and 20 respectively, between which `the sealing device I serves to seal the conveyor II. Gaskets 2I of any conventional type are employed between the flanges I3 and I1 or I4 and I8.

The linearly-moving mechanism II which the sealing device II! seals during its passage from the conduit I9 to the conduit 20 or vice versa, may consist either of a conveyor moving-in one direction or a plunger moving in av reciprocating path for feeding or pumping materials. For convenience of illustration, the linearly-moving mechanism II of Figure l has beenl illustrated as embodying a chain-mounted night conveyor having a chain generally designated 22 carrying spaced flight units generally designated 23. The chain 22 consists of spaced pairs of inner links 24 which at their opposite ends are pivotally connected to spaced outer links 25 (Figure 2) by means of pivot pins 26 which likewise pass through ears 21 projecting at right angles'from approximately semi-circular clamping plates 2-8 mounted on opposite sides of disc-like nights 29 of elastic deformable material such as rubber or synthetic rubber.

Y The inner and outer links 24 and 25 are spaced apart from each other and sealed against the entrance of dust or foreign matter by means of resilient washers 39 (Figure 2) of elastic deformable material, such as rubber or synthetic rubber. The inner links 24 pass through suitable apertures (not shown) in the flights 29 which are optionally split along a portion of the diameter I.

as at 3l to facilitate insertion of the links 24 in these apertures. The clamping plates 28 are also formed as right-hand or left-hand units and are provided with oppositely-facing cutaway portions 32 for the reception of the links 24 and 25 and the formation of the ears 21. The nights 29 and clamping plates 28 are held together in assembly by tie members 33 passing therethrough. The pivot pins 23 are held in assembly by cotter pins 34 or other equivalent devices mounted in the ends opposite their heads (Figure 2).

The sealing device I8 includes a double-walled tubular member generally designated 35 of elastic deformable material s'u'ch as rubber or synthetic rubber having a relatively thin outer wall 36 and av relatively'v thick. inner wall 31 separated by an annular air space or air chamber 38. The outer and inner' walls 35 and 31 are joined at one 'end by a connecting w'all I39 and at the other end by spaced end walls 40 and 4I (Figure 1) interconnected by an annular wall 42. The Walls 49, 4I and:4 42 in effect-form end nanges which are held between the casing and conduit flanges I3 and I1 by the bolts I5. The casing I2 is provided at 43 with an opening through which emerges a tubular portion 44 projecting from the outer wall 35 and leading into the air chamber 38. A filling connection and valve 45 with: a valve stem 46 therein serves for the attachment of a compressed air hose for nlling the chamber 38 with compressed air, a branch pipe 41 leading to a pressure gauge 48, the needle 49 of which indicates the pressure in the air chatnber 38 by means of a graduated dial 50 (Figure 1).

In order to reinforce the inner wall 31 and prevent it from piling up, wrink-ling or undulat- `ing during the passa-ge of the conveyor II therethrough, the double-walled tubular member 35 includes a reinforcing structure generally ydesignated 5I and shown isometrically in Figure 3, certain of the reinforcing rods therein .being omitted to avoid concealing the rods lying behind them. The reinforcing structure lconsists of a pair of spaced annular members or heads 52 and 53, the former extending radially outward a greater distance than the'A latter and provided with circumferentially-spaced holes 54 fory the passage of the bolts I5. The annular members 53 on their internal walls are'provided with ciroumferentially-sp'aced longitudinal 'grooves f or notches 55 for' the reception of the `straight ends 55 of longitudinal reinforcing'rods'51'of' spring steel or the like. 'The opposite'ends 58 of the rods'51 are curved or hooked, and pass through circumferentially-spaced internal notches 59 in the head 52 and theirti'ps are lodged in circumferentially-spaced holes 69 aligned radially with the notches 59 (Figure 3) From an examination of Figures 1 and 2 it will be seen that the tubular member 35 is molded over the reinforcing structure' '5| in' such a Way that the reinforcing rods 51 lie`within the inner wall 31. The right-hand end wall 39 is molded around the head or annular member 53 whereas the left-hand end nanges 40 and 4I and the' connecting portion 42 aremolded around the head or annular` member 52.

v The modified sealing device generally designated 5I shown, in Figure 4 is a simplification of the sealing device I0 shown in Figures 1 and 2 and lacks the reinforcing structure 5I shown in Figure 'It is also shown as sealingv a cablemounted night conveyor, 4generally designated 62, although the chain-mounted night-conveyor II of Figure 1 or a reciprocating piston feeder (not shown) might also be employed. The night conveyor 32 consists of a flexible cable 63 upon which disc-like nights 64 are mounted at spaced intervals. The flexible cable 63 is optionally provided with a tubular coating 63a'. of rubberlike material to protect it from corrosion or'wear. The night conveyor 52 is conventional and :its details form no part of the present invention, as several different types of conveyor may be used.

The simplified sealing device 6I includes a tubular'casing 65'ha`ving an annular inlet member 55 threaded as at 61 into 'one'en'd of the casing 8|. The inlet member 65 is provided with a funnel-shaped' or bell-mounted inlet 68 terminating in an internal end wall 59.

Threaded as at -19 `,upon the opposite end of the casing 65 is a flange 1I which is bolted as at 12 through annular gaskets 13 and 14 to the end wall I5 of'an inclined sludge tankgenerally designated 'IS (Figure). The tank 'I6 has side Walls '|'I and an inclined bottom wall 'I8 with a lip 'I9 at the top thereof for the discharge of the sludge carried upward along the bottom wall lrby the flight conveyor 62. The latter passes over grooved wheels 89 and 8| mounted on shafts-82 and 83 respectively at the opposite ends thereof and is maintained in a taut condition by means of an adjusting wheel 54 mounted on an adjustable shaft t5. The tank 'I3 contains a sludge bearing liquid 86, the sludge from which'settles to the bottom and is withdrawn by the-upwardlymoving flight conveyor 5.22, and .dumped over the lip 'I9 into a suitable receiver.

In order to seal the flights 554 ofthe flight conveyor 52, as they enter the tank I6 through the hole 8'! in the end wall 'i5 thereof (Figure 4), a double-walled tubular member 88 is mounted inside the tubular housing 65 and has outer and inner walls 83 and 90 respectively joined byend walls I and Ill! respectively. rfhe end-wall |00 abuts the end surface 69 of the inlet member 66 whereas the end wall iI abuts the inner surface or" the annular gasket 73. The outer `wall 89 is provided with an outwardly projecting tubular portion Iil2 which projects through the bore of a corresponding tubular portion |033 of the casing E5. The latter is provided with a valve member IM and a threaded connection |95 for a compressed air hose by which the annular air chamber |36 between the outer and inner walls 89 and V'eil is filled with compressed air.

The installation shown in Figure 7 consists of a vertically elongated tank Il which contains a sludge bearing liquid or drymaterial which it is desired to unload from the bottom thereof. For this purpose, two sealing devices I0 or BI are mounted on opposite sides of the tank |01 adjacent the inlet and exit'holes of the flight conveyor indicated diagrammatically by the chain line |63. Conduit-s |09 and IID connected to the sealing vdevices I0 or 3| serve to guide the conveyor |03 and carry away the material conveyed thereby.

r)The installation shown in Figure 8 also employs a vertical tank III similar to the vertical tank I'! and for a similar purpose. In the arrangement shown in Figure 8, however, only one sealing device Ill or 6| is employed, this being mounted at the inlet aperture in the sidewall of the tank An upwardly-curved conduit 2 extends from the outlet aperture in the opposite side wall of the tank I l up to a pointabove the liquid level IIS in the tank III and consequently also the liquid level in the conduit I I2. The flight v conveyor IIll passes through the sealing device I0 or 6| thence through the tank'I I3 and upward through the inclined conduit ||2, dumping the sludge conveyed thereby at the top end ||5 'of the conduit Il2. Wheels or sprockets |I6, H'I and |18 mounted on shafts IIS, |20 and |2| respectively serve to guide-the flightconveyor ||4 around its course, further guidance being provided by the curved portion |22 of 'the-upwardlyinclined conduit ||2.

'Operation In the operation of the invention, either ofthe sealing device II! shown in Figure 1 or the simplified sea-ling device shown in Figure 4, the 'air lchamber 38 or |05 is sup-plied with compressed air through the connection 45 or |05 until the inner wall 3l or S3 closely hugs the conveyor flights29 or 64. The chain lines |23 in Figure 1 indicate the -approximate position of the inner surface of the-inner wall A3'I when the air chamber 33 has been filled with compressed air. When the'conveyor or 62 is now started in motion along its linear path of travel, it slides along the inner wall 3'! or 9|! and is effectively "sealed by the tightengagement thereof due to the air pressure within the annular air chambers 38 or |06. The cage-like reinforcing structure 5| prevents undue and undesired deformation of the sealing device ||7 under heavy duty conditions .where the sealing device 6| (Figures 4 and 5) would be unsuitable.

As the flight conveyor II or 62 passes into the interior of the tank, container or compartment, such as the tanks 16, |01 or I|| of Figures 6,.'7 and 8 respectively, the pressure of the liquid within the tank is eifectively counteracted by the pressure of the air within the annular air chamber 38 or |06 sothat leakage is effectively prevented. The air pressure within the'air chamber 33 or |06 may beincreased or decreased as the conditions demand, according to the pressure arising bythe head of the liquid in the tank. The action of the conveyor and sealing device in the particular installations shown in Figures 6, 7 and8 has been described above in connection with the description of the construction thereof.

As previously stated, instead of conveying sludge from the bottom of a tank containing liquid, the invention` is equally applicable to sealing .oiT a compartment containing gas under pressure such as a dust-collector or a pressurized rebox to which pulverized coal is being'fed by the conveyor. The sealing device of the present invention not only prevents leakage but also because of its construction from elastic deformable material reduces wear, substantially cuts 'down noise and vibration, and in the ,presence of a liquid is self-lubricating due to the lubricating action of water upon rubber, or rubber-like materials. Where 'the sealing device is used in the presence of oil or other chemicals which attack natura-l rubber., it is preferable to employ a synthetic rubber which is resistant to such deteriorating action.

In Figure l the direction of travel of the `con veyor is from left to rightas indicated by the arrow. When heavy frictional loads develop, they are sustained by the flange structure i3, I 1, '49, 4|, 52 which is so designed for'that purpose.

While the infiatable chambers 38 and |06 have been described 'as lled with a compressed gas, it will beunderstood that they may be filled with a rliquid where an additional expansion chamber is provided forthe liquid to overcome its natural incompressibility. Alternatively, the opposite ends of the chamber may be interconnected by a by-pass conduit since the liquid will tend to move within the sleeve 31 or 90 'along with the movements of the nights 23 or 64 of the conveyor.

The `above-mentioned expansion chamber may consist -of a sack of elastic deformable material, such as rubber, connected to the chamber 38 or |06.

What I claim is:

l. A self-sealing conveyor construction conipris'ing an iniiatable elongated conduit having spaced fluid-.tight .outer and inner walls forming an inflatable vchamber therebetween, said inner wall being tubular and of elastic deformable material, .an elongated resilient reinforcing structure embedded in said inner wall outwardly of the inner surface thereof, anr elongated longitudinally-movable element disposed in said con- 7 duit, and an enlarged material-conveying member mounted transversely on said element in peripheral engagement with said inner surface of said inner wall.

2. A self-sealing conveyor construction comprising an iniiatable elongated conduit having spaced fluid-tight outer and inner walls forming an Viniiatable chamber therebetween, said inner wall being tubular and of elastic deformable material, an elongated resilient reinforcing structure comprising an annular framework of longitudinally-extending rods embedded in said inner wall outwardly of the inner surface thereof, an elongated longitudinally-movable element flisposed in said conduit, and an enlarged materialconveying member mounted transversely on said element in peripheral engagement with said inner surface of said inner wall.

SQA self-sealing conveyor construction com' prising an inflatable elongated conduit having spaced fluid-tight outer and inner walls forming an'inflatable chamber therebetween, said inner wall being tubular and of elastic deformable material, an elongated resilient reinforcing structure comprising a pair of spaced annular heads and' an annular framework of longitudinallyextending rods embedded in said inner wall outwardly of the inner surface thereof and interconnecting said heads, an elongated longitudinally-movable element disposed in said conduit, and an enlarged material-conveying member mounted transversely on said element in peripheral engagement with said inner surface of said inner wall. t

4. A self-sealing conveyor construction comprising an inflatable elongated conduit having spaced fluid-tight outer and inner walls forming an inatable chamber therebetween, said inner wall being tubular and of elastic deformable material, an elongated resilient reinforcing structure comprising a pair of spaced annular heads and an annular framework of longitudinallyextending rods embedded in said inner wall outwardly of the inner surface thereof and interconnecting said heads, one of said walls having a transversely-extending iiange engaging one of vsaid heads, an elongated longitudinally-movable element disposed in said conduit, and an enlarged material-conveying member mounted transversely on said element in peripheral engagement with said inner surface of said inner wall.

5. A self-sealing conveyor construction comprising an elongated duid-tight casing, an innatable conduit of elastic deformable material mounted within said casing and having spaced tubular outer and inner walls forming an inflatable chamber therebetween, an elongated longitudinally-movable element disposed in said conduit, and an enlarged material-conveying member mounted transversely on said element in peripheral engagement with said inner wall, said casing having a flanged portion, and said outer and inner walls having an inter-connecting end portion at one end thereof and having flanged portions connected to said casing fianged portion at the other end thereof.

6. A self-sealing conveyor construction comprising an elongated fluid-tight casing, an inatable conduit of elastic deformable material mounted within said casing and having spaced tubular outer and inner walls forming an inflatable chamber therebetween, an elongated resilient reinforcing structure comprising an annular framework of longitudinally-extending rods embedded in said inner wall outwardly of the inner D d surface thereof, an elongated longitudinally-movable element disposed in said conduit, and an enlarged material-conveying member mounted transversely on said element in peripheral engagement with said inner surface of said inner wall.

7. A self-sealing conveyor construction comprising an elongated Huid-tight casing, an inilatable conduit of elastic deformable material mounted within said casing and having spaced tubular outer and inner walls forming an innatable chamber therebetween, an elongated resilient reinforcing structure comprising a pair of spaced annular heads and an annular framework of longitudinally-extending rods embedded in said inner wall outwardly of the inner surface thereof and interconnecting said heads, an elongated longitudinally-movable element disposed in said conduit, and an enlarged material-conveying member mounted transversely on said element in peripheral engagement with said inner surface of said inner wall.

8. A self-sealing conveyor construction comprising an elongated huid-tight casing, an inflatable conduit of elastic deformable material mounted within said casing and having spaced tubular outer and inner walls forming an inflatable chamber therebetween, an elongated resilient reinforcing structure comprising a pair of spaced annular heads and an annular framework of longitudinally-extending rods interconnecting said heads, and embedded in said inner wall outwardly of the inner surface thereof, one of said rwalls having an outwardly extending portion engaging one of said heads, an elongated longitudinally-movable element disposed in said conduit, and an enlarged material-conveying member mounted transversely on said element in peripheral engagement with said inner surface of said inner wall.

9. A self-sealing conveyor construction comprising an elongated fluid-tight casing, an inatable conduit of elastic deformable material mounted within said casing and having spaced tubular outer and inner Walls forming an innatable chamber therebetween, an elongated resilient reinforcing structure comprising a pair of spaced annular heads and an annular framework of longitudinally-extending rods connected to said inner wall and interconnecting said heads,

Aan elongated longitudinally-movable element disposed in said conduit, and an enlarged material-conveying member mounted transversely on said element in peripheral engagement with said inner wall, said casing having a flanged portion and said outer and inner walls having an inter-connecting portion at one end thereof and flanged portions at the other end thereof engaging one of said heads and secured to said casing anged portion.

HENRY W. HAPMAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,048,019 Wilson Dec. 24, 1912 1,554,275 Good Sept. 22, 1925 2,428,995 Rogers Oct. 14, 1947 2,478,326 Scarth Aug. 9, 1949 FOREIGN PATENTS Number Country Date 834,316 France Aug. 16, 1938 

